820470 has 32 divisors (see below), whose sum is σ = 2251008. Its totient is φ = 187488.

The previous prime is 820459. The next prime is 820481. The reversal of 820470 is 74028.

It is a happy number.

820470 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (820459) and next prime (820481).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

820470 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1744 + ... + 2163.

It is an arithmetic number, because the mean of its divisors is an integer number (70344).

2⁸²⁰⁴⁷⁰ is an apocalyptic number.

820470 is an abundant number, since it is smaller than the sum of its proper divisors (1430538).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

820470 is a wasteful number, since it uses less digits than its factorization.

820470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3924.

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 820470 is about 905.7979907242. The cubic root of 820470 is about 93.6168955548.

Adding to 820470 its reverse (74028), we get a palindrome (894498).

The spelling of 820470 in words is "eight hundred twenty thousand, four hundred seventy".